By Marcus Lindqvist · Updated September 23, 2026 · 5 min read
Short answer
In 2026 the US HFC rules under the AIM Act reach industrial refrigeration: new process chillers and industrial systems face GWP limits, and leak repair and automatic leak detection requirements took effect on January 1, 2026. Existing equipment can keep running on its current refrigerant, and a May 2026 EPA rule pushed some deadlines, such as cold storage warehouses, out to 2032 with interim limits.
For US chillers and industrial refrigeration, 2026 is the year the HFC transition stops being mostly about residential air conditioning. The rules come from the American Innovation and Manufacturing (AIM) Act of 2020, which EPA implements in three parts: a phasedown of HFC production and imports, restrictions on HFCs in new equipment (Technology Transitions), and rules for leaks and reclaimed refrigerant (Emissions Reduction and Reclamation). Rules are changing quickly: this is a general overview, not compliance advice, so always check the current EPA pages and the Federal Register text.
How much HFC is still being produced?
The AIM Act phases down US production and consumption of HFCs, measured in CO2-equivalent, against a historic baseline. Since 2024 the allowed level has been 60 percent of that baseline, and the next step, to 30 percent, is scheduled for 2029. The step-downs continue after that until the level reaches 15 percent of the baseline in 2036.
The practical effect is supply and price pressure on high-GWP refrigerants such as R-404A, R-507A and R-410A, which makes reclaimed refrigerant and leak prevention more important every year.
Which new equipment faces GWP limits in 2026?
EPA’s Technology Transitions rule, finalized in 2023, sets maximum global warming potential (GWP) limits for refrigerants in new equipment, by sector. It applies to new systems and installations, not to equipment that is already operating. Before the May 2026 revisions described below, the key points for commercial and industrial users were:
- Chillers for comfort cooling: a 700 GWP limit applies to new stand-alone chillers manufactured or imported from January 1, 2025.
- Industrial process refrigeration chillers with a leaving fluid temperature at or above −22 °F: a 700 GWP limit from January 1, 2026. Lower-temperature process chillers have a later date, and the coldest applications are not covered.
- Industrial process refrigeration without chillers: limits depend on the refrigerant charge and the evaporator temperature. For example, a new system with 200 lb or more of charge in the higher-temperature range faces a 150 GWP limit from January 1, 2026 (the high-temperature side of a cascade system is treated separately).
- Cold storage warehouses: originally 150 or 300 GWP, depending on the charge size, from January 1, 2026.
A limit of 700 GWP rules out R-134a, R-410A and R-404A in new equipment in those categories. A limit of 150 practically means natural refrigerants such as ammonia and CO2, hydrocarbons in small charges, or HFO-based options.
What did EPA change in May 2026?
In May 2026 EPA finalized a rule reconsidering parts of the Technology Transitions program. It extends some compliance dates but, according to EPA and industry summaries, does not change the long-term GWP limits. The main points relevant to refrigeration are:
- Cold storage warehouses: the 150 or 300 GWP limits now apply from January 1, 2032. Until then an interim limit of 700 GWP applies, which still excludes R-404A, R-507A, R-448A and R-449A.
- Retail food refrigeration: supermarket systems and remote condensing units get later deadlines for the final limits and an interim limit of 1,400 GWP.
- Semiconductor manufacturing: certain industrial process refrigeration chillers and equipment used in semiconductor plants now have a January 1, 2030 date.
- Residential and light commercial air conditioning: the deadline for installing systems built with higher-GWP refrigerants before 2025 was removed.
Industrial process refrigeration outside semiconductor manufacturing was not part of these extensions in the summaries we reviewed, so the 2026 dates above still apply to it.
What do the leak rules require from 2026?
EPA’s Emissions Reduction and Reclamation rule, finalized in 2024, brings leak management for HFCs closer to the older Section 608 rules for ozone-depleting refrigerants. From January 1, 2026:
- Leak repair requirements apply to appliances holding 15 lb or more of an HFC or substitute refrigerant with a GWP above 53. Owners must calculate leak rates when refrigerant is added and repair leaks above the applicable threshold within set time frames.
- Automatic leak detection is required on new commercial refrigeration and industrial process refrigeration systems with a charge of 1,500 lb or more. Certain existing systems of that size have until January 1, 2027.
- Recordkeeping of refrigerant additions, leak rate calculations and repairs is part of the rule.
Ammonia (R-717) and CO2 (R-744) are not covered by these HFC leak rules because they are not HFCs and their GWP is very low. Ammonia systems remain subject to their own safety rules, such as OSHA Process Safety Management for large charges and the IIAR standards.
How do common refrigerants compare?
| Refrigerant | Type | GWP (approx.) | ASHRAE 34 safety class | Status for new equipment in limited sectors |
|---|---|---|---|---|
| R-404A / R-507A | HFC blend | about 3,900 | A1 | Above all industrial and cold storage limits |
| R-410A | HFC blend | about 2,090 | A1 | Above the 700 limit |
| R-134a | HFC | about 1,430 | A1 | Above the 700 limit |
| R-448A / R-449A | HFC/HFO blend | about 1,390–1,400 | A1 | Above the 700 limit; below the 1,400 interim retail limit |
| R-513A | HFC/HFO blend | about 630 | A1 | Below 700; above 150 and 300 |
| R-454B | HFC/HFO blend | about 470 | A2L | Below 700; above 150 and 300 |
| R-1234ze(E) | HFO | below 10 | A2L | Below all limits |
| R-717 (ammonia) | Natural | 0 | B2L | Below all limits |
| R-744 (CO2) | Natural | 1 | A1 | Below all limits |
GWP values are approximate 100-year values; check EPA’s tables for the figure that applies to a specific rule.
What does the safety class mean for system design?
ASHRAE Standard 34 classifies refrigerants by toxicity (A lower, B higher) and flammability (1, 2L, 2, 3). Many low-GWP replacements are A2L (mildly flammable), which brings requirements for machinery rooms, ventilation, leak detection and charge limits under ASHRAE Standard 15 and the model codes.
What does this mean for existing plants?
Nothing in the 2026 rules requires an existing chiller or refrigeration system to stop running or be converted. The pressure is indirect: tighter supply of high-GWP refrigerants, stricter leak management, and GWP limits when a system is replaced or significantly expanded.
Our team in Ukraine works with ammonia screw compressors and with HFC refrigeration for a national grocery chain, under European F-gas rules that pushed a similar transition earlier. If you work on industrial refrigeration in Central Texas, we would like to meet you. See our open positions or partnership options.
How do you turn these changes into a plan?
The regulatory picture is easier to handle if it becomes a simple inventory exercise.
- List every system with refrigerant type, charge, age and location.
- Flag high-risk items: systems using R-404A or R-22, systems that leak often, and equipment near end of life. The detailed pathways are in R-404A replacement with R-448A and R-449A and the R-410A timeline.
- Check the legal background in what the AIM Act requires and the Technology Transitions update.
- Understand A2L handling before specifying new equipment; see A2L refrigerants explained.
- Budget by lifecycle, not by deadline: replacing equipment at its natural end of life is usually cheaper than an early forced change.
Keep records of each decision, and revisit the inventory annually. Confirm current requirements at epa.gov.
Frequently asked questions
Do I have to replace my R-404A or R-134a system in 2026?
No. The AIM Act rules restrict refrigerants in new equipment and set leak management requirements, but they do not ban the use of existing systems. Those systems can be maintained and recharged, although refrigerant availability and price will keep tightening as the phasedown continues.
Is R-22 affected by the AIM Act?
R-22 is an HCFC, not an HFC, so it is covered by the older ozone-protection rules under the Clean Air Act rather than the AIM Act. Production and import of new R-22 ended in 2020, and existing systems rely on recovered, reclaimed or stockpiled refrigerant.
Is ammonia a safe choice under the new rules?
Ammonia has zero GWP and is not restricted by the HFC rules, which is why it remains the main refrigerant for large industrial plants. It is toxic and flammable at certain concentrations, so systems must follow ASHRAE 15, IIAR standards and, above certain charges, OSHA Process Safety Management.
